.8,,. GEOLOGY OF THE CENTRAL HIMALAYA. 445 



pods, as well as Corals and Encrinites, also await determination. 

 We must therefore suspend judgment concerning the European 

 equivalents of these strata, and the same remarks apply to succeeding 

 formations of Coral-limestone, Crinoid-limestone, white quartzite, and 

 limestone, that are said to rest conformably on the older strata, and to 

 represent formations from the Lower Devonian to the Upper 

 Carboniferous. The Hmestones are variable in thickness, and the 

 entire series varies from 1,450 to 2,500 feet. In the rocks grouped as 

 Devonian there are OrtJioceras and ProdticUis seviireticulatus. 



The occurrence of Athyris royssii and of Prodtichis in the highest 

 band of limestone affords the only particular evidence stated of its 

 Carboniferous age. The distribution of the highest Carboniferous 

 beds affords evidence in overlaps of physical changes of a widespread 

 nature, and the author remarks that perhaps no other formation in 

 Asia has a wider area of distribution. He lays perhaps too much 

 stress on the lithological change between the beds grouped as 

 Carboniferous and those regarded as Permian : even abrupt changes 

 from quartzites associated with limestone to " crumbling black 

 shales" afford no criterion oi great physical changes as proved by the 

 record of our British Carboniferous rocks. The fact, too, that the 

 succeeding beds in the Himalaya consist of Prod actus -beds of Permian 

 age (yielding a form near to Prodiictus latirostratns) tends to show, as 

 the author admits, that the break could have been of no great extent 

 as regards time. The evidence of a break lies chiefly in the uptilting 

 and partial erosion of the Upper Carboniferous beds, so that successive 

 strata are overlapped in an unconformable manner by Permian rocks. 

 Thus the Carboniferous beds, which are purely marine, are followed 

 by a great system of strata that are in a large measure littoral ; and 

 the author considers that the wrinkling process, which resulted in the 

 elevation of the Himalaya, was partially brought about in Permian 

 times, so that the main outUnes of the great range, which had 

 previously been determined, were then more distinctly foreshadowed. 



The older rocks are regarded as forming a continuous series ; 

 and now, after the unconformity just mentioned, we find the records 

 of another sequence from the Permian shales to Liassic limestones. 

 The Permian beds exhibit a thickness only of 120 to 250 feet, but 

 they have suffered much from crushing and folding, and the more 

 rigid Triassic rocks have been thrust over them on to the Car- 

 boniferous formations. Passage-beds occur between the Permian and 

 Trias containing a fauna akin to both, and noted as the Otoceras 

 horizon, or zone of 0. woodwardi. The Triassic rocks attain a thick- 

 ness of from 1,500 to 4,000 feet, and consist mainly of limestones and 

 shales. They are divided into Bunter, Muschelkalk, and Keuper, 

 and are characterised by fossil zones, of which Brachiopods are 

 the chief indices. Casts of Corbis occur in the Upper Trias, and in 

 some of the beds Cevatites and Avcestes are preserved. The author 

 remarks that a great likeness exists between the Trias and Rhaetic 



